1. Field of the Invention
The present invention relates to a multicast/broadcast service (MBS). More particularly, the present invention relates to a method of providing an MBS using a Wireless Broadband Internet/Worldwide Interoperability for Microwave Access (WiBro/WiMAX) network, and a system using the method which can provide a terminal which is connected to the WiBro/WiMAX network with the MBS.
2. Description of Related Art
A Wireless Broadband Internet/Worldwide Interoperability for Microwave Access (WiBro/WiMAX) network communicates in a unicast manner when providing voice and data services. When application services which require a quality of service (QoS), such as voice and video phone services, are requested in a mobile terminal, the request is received in an application layer. A policy function (PF), which controls a QoS with respect to access networks, is requested for the QoS. Also, the PF requests WiBro/WiMAX access networks for the QoS, and provides the QoS in a network layer.
However, when users select a particular IPTV channel in MBS services such as an Internet protocol television (IPTV) service, a mobile terminal transmits a message, including a multicast Internet protocol (IP) address corresponding to an IPTV channel, to WiBro/WiMAX access networks. In this instance, the message including the multicast IP address, may be an Internet group management protocol (IGMP) message in the case utilizing Internet Protocol version 4 (IPv4), and a multicast listener discovery (MLD) message in the case utilizing Internet Protocol version 6 (IPv6).
The WiBro/WiMAX access networks which receive the IGMP/MLD message selects and transmits an IP multicast stream, which is identical to a multicast IP address included in the IGMP/MLD message, to a terminal. In this case, although multiple IPTV users simultaneously select the same IPTV channel, a single IPTV stream is transmitted to a terminal in a multicast method.
In IPTV services, unlike voice and video phones in a unicast manner, a service request from a terminal is not received in the application layer. In IPTV services, the IGMP/MLD message is received in the WiBro/WiMAX access networks, and the multicast stream is transmitted to the terminal. Accordingly, a new QoS provisioning structure, which is different from a QoS provisioning structure which is applied to an application service in a unicast manner, is required.
In the IPTV services described above, a single IP multicast stream corresponding to an IPTV channel is transmitted to a plurality of mobile terminals in a multicast method. Accordingly, a method of providing a QoS with respect to the IP multicast stream corresponding to each IPTV channel is provided, as opposed to a method of providing a particular mobile terminal with the QoS.
Also, when performing an authorization for the IPTV services in the same method as a Multimedia broadcast/Multicast service (MBMS), the WiBro/WiMAX access networks are required to perform service authorizations with an IPTV control node every time mobile terminals receive the IGMP/MLD message which requests an IPTV channel change. Specifically, whenever the mobile terminals change channels, the service authorizations are required to be performed through an interoperation between the WiBro/WiMAX access networks and the IPTV control node. Accordingly, a channel change such as a change to an existing TV broadcast, may not be performed quickly.
Accordingly, a new IPTV service authorization system and method, which is different from a service authorization provided in the 3rd Generation Partnership Project (3GPP) MBMS, is required to provide a fast channel change of IPTV services in the WiBro/WiMAX access networks.